[L] Change in coreboot[master]: mb/purism/librem_l1um_v2: Add support for Purism Librem L1UM v2

[Jonathon Hall (Code Review)]

Attention is currently required from: Angel Pons, Felix Singer, Martin L Roth, Matt DeVillier, Michael Niewöhner, Tim Wawrzynczak.

Jonathon Hall has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/75090?usp=email )

Change subject: mb/purism/librem_l1um_v2: Add support for Purism Librem L1UM v2
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Patch Set 5:

(1 comment)

File src/mainboard/purism/librem_l1um_v2/bootblock.c:

https://review.coreboot.org/c/coreboot/+/75090/comment/c2fd6a83_d5b0b63b :
PS5, Line 23: 	/*
> Does this need to happen on every boot, or just when you need the serial console? […]

Thank you Martin, saved draft but forgot to click "reply"

The BMC also seems to reset the TPM during its own startup, so the failing to wait for it to finish sometimes meant the TPM would disappear and not be visible to the OS.